<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>DOM 1</title>
    <style>
        .red{
            background: red;
        }
    </style>
</head>
<body>
    示例
<div>
    <div id="test"><span>test1</span><p class="red">段落标签3</p>test2
    </div>
</div>
<div id="test2">
    <p class="red">段落标签3</p>test2
</div>
</div>
    
<div id="empty">
    <div id="e1"></div>
    <div id="e2"></div>
    <div id="e3"></div>
</div>
<div id="siblings">
    <div id="s1"></div>
    <div id="s2"></div>
    <div id="s3"></div>
</div>
<div id="travel">
    <div id="t1">t1</div>
    <div id="t2">t2</div>
    <div id="t3">t3</div>
</div>
    <script src="dom.js"></script>
    <script src="main.js"></script>
</body>
</html>